Electrical fuse



Aug. 21, 1928.

. 1,681,239 c. A. JOHNSON r AL ELECTRICAL FUSE FiI ed Nov. 7, 1924 ficnreq ,Dana Harm 1211/,

Patented Aug. 21, 192 8.

UNITED STATES PATENT OFFICE. I

onns'rlm A. JOHNSON AND HERVEY DANA HARLAND, or onrcneo, ILLINOIS, .AS-

SIGNORS TO CHICAGO FUSE MFG. COMPANY,

' TION or ILLINOIS.

OF CHICAGO, ILLINOIS, A CORPORA- ELECTRICAL FUSE.

Application filed November 7, 1924. Serial No.- 748,366.

Our invention relates to improvements in electrical fuses and more.specifically to fuses for carrying small currents such as are utilizedto heat the filaments of radio vac uum tubes. j g

One object of our invention is to provide a fuse of simple and improvedconstruction form of a cylindrical transparent dome exin which the fuseelement is mounted on a pair of spaced contact members withintransparent dome.

Another object is to provide ,an inexpensive fuse cartridge havingupright fuse supporting members to which a fuse element can beconveniently attached and yieldable contact membersgvhich extend beyondthe periphery of 'a protecting dome.

A further object is to provide a complete fuse unit comprising aremovable cartridge with yieldable contact members and a novel cartridgemounting having a pair of grooved spring arms for engaging said contactmembers to support the cartridge in upright rigid position.

Other objects and advantages will be apparent from the followingdescription.

In the accompanying drawings, Figure l is a vertical sectional view of afuse and mounting embodying the features of our invention.

Fig. 2 is a .plan view of the mounting base,

Fig. 3 is a plan view of the fuse cartridge.

Fig. 4 is a fragmentary view of one con- .tact member showing the mannerof supporting the fuse element.

In the exemplary embodiment illustrated in the drawings, 10 represents apair of upright metallic contact members mounted in a plug 11which-comprises, in the present instance, a plurality of apertured disksof suitableinsulating material. The members 10 are preferably U-shapedstrips eachhaving a long leg 12 and a short contact leg 13, the medialportion of the strips extending at right angles to the legs. Preferablythe long legs are herein deformed near, their central portions toprovide wedge-like projections 14. When the legs 12 are, forced throughrectangular apertures 15 in the disks 11, the projections 14 remainwedged therein and thus maintain the members -10 in upright parallelrelation. In this assembled position, the underside of the in sulatingmember abuts against the medial portion of the contact members andthereby holds the supporting legs against lateral movement. A notch 16is preferably provided' in the upper end of each leg 12to receive a fuseelement 17 which can be conveniently attached by solder.

Toenclose and protect the fuse element 17, We providea case 18preferably in the tending between the long legs 12 and the short legs 13to snugly receive-the plug 11' whichextend beyond'the periphery of thedome 18.

It will be apparent that the elements thus upper. ends of the contactmembers 10 while being supported thereon. 1 v

To insure good electrical contact the fuse cartridge can be forcedyieldingly into a suitable mounting. The mounting shown hereincomprisesan insulating base 19 and a palrof L-shaped clamping members 20 suitablysecured to the base by rivets 21.,

To receive the contact head of the fuse cartridge, a circular recess 22having two diametrically opposed notches 23 is provided in the base 19.,The members 20 have spring arms 24 which extend into the notches 23 inspaced relation to the ends of said notches, each spring arm] beingpreferably formed with projecting ribs 25 which define a groove 26 forreceiving the short legs 13 of the"contact members, Lead wires (notshown) can be connected to the ends 26 of the clamping members. Thus,when the fuse cartridge is inserted into the mounting, the spring arms24 engage the yieldable legs 13 of the contact members 10, and hold thecartridge in upright rigid position.

While we have shown in the drawings and described in detail thepreferred em-' bodiment of our invention, it should be understood thatsuch disclosure is made merely .for the purpose of illustration and thatother 5 modifications and Variations will probably occur to thoseskilled in the art. We aim in the appended claims to cover all suchlegltimate modifications and variations.

We claim as our invention:

1. An electrical fuse comprising, in combination, a pair of contactmembers each insulating plug fitting in the open end of said dome, twoU-shaped metallic members each having one leg projecting through saidplug into said dome, the other leg being extended beyond the peripheryof saiddome 'to form a yieldable contact, and a fuse element connectedto said legs within said (lome."-

3. An electrical fuse, comprising, in combination, a case, a pair ofcontact members each comprising two legs, one leg of each memberprojectin into said case with'the end thereof out o contact with thesupport for the -member,a fuse elementjoining the free ends of saidlastmentionedlegs within said case, the other two legs of said membersextending along the outer periphery of 40 said case.

bination, acase having an msulating member closing one end thereof, andtwo U- shaped metallic strips each having one leg passing through anaperture in said insulating member, the inner ends of the latter legsbeing joined by a fusible element, the other two legs of'said stripsextending along opposite siiles of-the outer periphery of said case inspaced relation thereto to provide yieldable contact terminals.

5. An electrical fuse unit comprising, in combination, an insulatingbase having a single recess therein, a pair of terminal clamping memberssecured to said base and having angular spring arms projecting into saidrecess, and a fuse cartridgeseated in said recess and having opposedresilient contacts extending longltudinally along the sides of saidcartridge and engaging said springarms and withdrawable therefrom byslidin movement in-pulling said cartridge out 0 said recess.

6. An electrical fuse unit comprising, in combination, a fuse cartridgehaving exterbination, a pair of metallic members each 4. An electrlcalfuse comprising, in comdisk receiving said supporting legs, an enclosingdome snugly receiving said plug each having one leg extending throughsaid plug into said dome and another leg extend-- 'nalyieldablecontacts" along the sides thereof, an insulating base having asingle recess to receive the contact end of said cartridge, a'pair ofclamping members secured to said. base and having spring armsproje'cting'into said recess and coacting with said .yieldable' contactsto support said cartridge. I f v 7. An electrical fuse unit comprising,in combination, a fuse cartridge having external contacts, an insulatingbase recessed'to receive said cartridge, two clamping members on saidbase each having a spring arm depending in said recess, and a pair oflonit'udinal ribs on each of said spring arms forming therewith a groovefor receiving said fuse contacts.

. 8. An electrical fuse comprising, in combination, a pair of metallicmemberseach' having afuse supporting legand a portion extending at rightangles to said leg with a contact terminal thereon, an insulating diskreceiving said supporting legs and abutting against'said rightangle-portions whereby to hold said supporting legs firmly in spacedrelation; a fuse-element joining said supporting legs, and a dome forprotecting said fuse element.

9. An electrical fuse comprising, in com-- having a fuse supporting legand a portion extending at right angles to said leg with a contactterminal thereon, an insulating disk receiving said supporting 'legs,and abutting against said right angle portions whereby to hold saidsupporting legs firmly in spaced relation, a fuse element joining saidsupporting legs, and a dome snugly receiving said disk. I

10. An electrical fuse comprising, in com bination, a pair of metallicmembers each having a fuse supporting leg and a portion extending atright angles to said leg with a; contact terminal thereon, an insulatingwithin its open end and abutting against the contact portions of saidmembers, and a fuse element joining said supporting legs within saiddome.

11. An electrical fuse comprising, in combination, a tubular dome, aninsulating plug 'of substantial thickness entered in one en of saiddome, a pair of flat metallic strips ing at right angles to said firstmentioned leg with a contact portion thereonand abutting against theouter surface of said plug, and a fuse element joining the ends of saldstrips within said dome.

12. An electrical fuse comprising, in combination, an insulating memberhaving apertures therein, metallic contact strips extending through saidapertures and having no lateral projections wedged into said aperturesto hold said strips firmly in said insulating member, a fuse elementjoining the ends of said strips, and means for enclosing said element. t

13. An electrical fuse comprising, in combination, a pair of fusesupporting contact members, means to support said members in uprightspaced relation, a fuse element extending across the upper ends of saidmembers and having its opposite ends soldered to said members, saidmembers having notches at their upper ends to hold said element on saidmembers during soldering, and a protecting case for said element.

14. An electrical fuse comprising, in combination, a hollow cylindricalcase, an insulating closure plug snugly fittinginto one end of saidcase, a pair of flat metallic members projecting through apertures insaid afiixed our signatures.

CHESTER A. JOHNSON.

HERVEY DANA HARLAND.

CERTIFICATE OF CORRECTION.

latent No. l, 681, 239.

Granted August 2i, Wi to I CHESTER A. JOHNSON ET AL.

, It is hereby certified that the above numbered patent was erroneouslyissued to "Chicago Fuse Mfg. Company, of Chicago, Illinois, aCorporation of llliis," whereas said patent should have been issued to"Chicago Jefferson Fuse & Electric Company, of Chicago, Illinois, aCorporation of Illinois", said coration being assignee of the entireinterest in said invention, as shown by the records of assignments inthis office"; and that the said Letters Patentshould be read with thiscorrection therein that the same may conform Patent 0ft ice.

to the record of the case in the Signed and sealed this 6th day ofNovember, A. ,D. 1928.

, (Seal) M. J. Moore, Acting Commissioner of Patents.

